From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E8D2449D5B7 for ; Thu, 17 Sep 2026 16:19:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789661967; cv=none; b=lawlBbgEyMe338LvVqrAR673oj25M1k4hLNJaglQWCHPj9XnjFsFQWuRuhkeMJ4G0DDRx2P/ABevZOkYx5J93sWmW4qkEPZ7Nnqzmlk3rjnVRfRT2FSkF4vSocGfI3JrdyPLRJZ2KHikpY9uzM361XrFu+tRRpTatUaFucXXGMw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789661967; c=relaxed/simple; bh=BCz6h2Q1bT2n9WknjE8zobs5IOb81n/wUbgYyX1Q0rc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=rq2kOM+YuqfgcsY2XyQtcxdJWAgZx+dMbe+7bl7NhVDY2bBeLtjoiEyZ4kTJYA2Jx5yK7TW/cSgPhrEon50pNHmYb5PYeK5SWGPLzJpmFqzhymB7j/KhbyD/dPFc+/V7S9OeEv4wVhAuHqSglqG3003ZQiXpXyAkARUGJe76qE4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=g6RTl6Xi; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="g6RTl6Xi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4BE7E1F000FF; Thu, 17 Sep 2026 16:19:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789661965; bh=hpltJqWlNQE7HyUtitrdsDRura1f438W2zBatcw13Io=; h=From:To:Cc:Subject:Date:Reply-To; b=g6RTl6XiDYRTmqUhm2eifDdpwelt68zHbywTE3AQNzVezmn3S4ZuSkLhTWKlgSBVY wVDzR1owmWkdiRnddHI8MDkp8zuK1TiIIkkPiVctHlDQS3YEo5GEangfzrOXNmFN2H xPhW2QnhaP33AJGDqBVnIeteplO7LNZsPZFVKyT8= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-90195: riscv, bpf: Fix missing sign-ext for signed 1-byte and 2-byte kfunc args Date: Thu, 17 Sep 2026 17:10:25 +0100 Message-ID: <2026091732-CVE-2026-90195-9bcf@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2920; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=BXQX6X+PP8pvmXEKGMCShEDEHZeEdFFPM3pSSdroM1g=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlrBBrnbb2+4XS/2hYR2zXLhELeam03qWZiFPnvsc/YM 5Hj7pSJHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjAR5VSG+Rl2YafEG0Nbeo+7 OH16O+t51AW+NQxzxR9biyzyeTFB97NHYm9ZwdF0U85rAA== X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: riscv, bpf: Fix missing sign-ext for signed 1-byte and 2-byte kfunc args On RV64, the ABI requires sign-extension for signed 1-byte and 2-byte kfunc args. However, the RV64 JIT currently does not perform sign-extension for such kfunc args. Before commit 7ce090afbf72 ("bpf: Infer zext_dst based on static register liveness analysis"), state pruning could potentially omit zero-extension of 32-bit subregisters, which inadvertently masked the above issue by making the args appear as if they had been properly sign-extended. After that commit, the problem is exposed, causing the kfunc_call/kfunc_call_test4 selftest to fail. Fix this by extending the existing sign-extension logic to handle signed 1-byte and 2-byte kfunc args as well. The Linux kernel CVE team has assigned CVE-2026-90195 to this issue. Affected and fixed versions =========================== Issue introduced in 6.9 with commit 443574b033876c85a35de4c65c14f7fe092222b2 and fixed in 6.12.110 with commit 555fc6f1caf00ce7005e732b688da26c0dc3c5c5 Issue introduced in 6.9 with commit 443574b033876c85a35de4c65c14f7fe092222b2 and fixed in 6.18.52 with commit 801ae90f8ce099187e6224cec7d72d07a4df0324 Issue introduced in 6.9 with commit 443574b033876c85a35de4c65c14f7fe092222b2 and fixed in 7.2.6 with commit 71dbd143be598954ae103feadd12692aeb0f2f88 Issue introduced in 6.9 with commit 443574b033876c85a35de4c65c14f7fe092222b2 and fixed in 7.3-rc1 with commit f2aaa621591093cfe8224a25ef2f04a3b1e304b0 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-90195 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: arch/riscv/net/bpf_jit_comp64.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/555fc6f1caf00ce7005e732b688da26c0dc3c5c5 https://git.kernel.org/stable/c/801ae90f8ce099187e6224cec7d72d07a4df0324 https://git.kernel.org/stable/c/71dbd143be598954ae103feadd12692aeb0f2f88 https://git.kernel.org/stable/c/f2aaa621591093cfe8224a25ef2f04a3b1e304b0